Back frame and backlight system

ABSTRACT

The present invention provides a back frame of flat panel display device, which includes primary assembling pieces, secondary assembling pieces, and a bracing piece for fixing a circuit board. The primary assembling pieces have a number of at least two, and the at least two primary assembling pieces are connected through joining. The secondary assembling pieces are joined to the primary assembling pieces. The bracing piece includes a bracing body, a first suspension section, a first bearing section, and a first resilient bent section. The bracing body is mounted to the primary assembling pieces or the secondary assembling pieces or is mounted to both the primary assembling pieces and the secondary assembling pieces. The available mounting points between the bracing body and the primary assembling pieces or the secondary assembling pieces are of a number of at least two. The bracing piece fixes a circuit board. The present invention also provides a backlight system. The back frame and the backlight system of the present invention have a back frame mold having a simple structure, reduce the expenditure of a back frame mold, and save the material used for back frame so as to lower down the cost of flat panel display device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of displaying techniques, andin particular to a back frame of a flat panel display device and abacklight system.

2. The Related Arts

The state-of-the-art liquid crystal display device comprises a frontbezel, a panel, and a backlight module, of which the backlight modulecomprises a back frame, a reflector plate, a light guide, and a lightingassembly.

Currently, a variety of display panels of different sizes are availablein the market to meet different needs of general consumers. For example,in the field of television set, the sizes of liquid crystal panelsinclude 31.5, 42, 46, 48, and 55 inches. Different back frame molds areprovided for liquid crystal planes of different sizes.

Referring to FIG. 1, FIG. 1 is a schematic view showing a conventionalback frame of liquid crystal display device. As shown in FIG. 1, theconventional back frame 10 is a unitary back frame, and it is often thata unitary back frame 10 is made with metal stamping or plastic injectionmolding. The unitary back frame 10 consumes much material and has a highmaterial cost. Further, a large-sized back frame 10 requires large-sizedstamping equipment, and the size of mold corresponding to such a backframe 10 is large and the structure complicated, making the expenditureof the back frame mold high. As a consequence, the conventional backframe is of a high cost.

SUMMARY OF THE INVENTION

The technical issue to be addressed by the present invention is toprovide a back frame and a backlight system, which lower material costand mold cost.

To address the above technical issue, the present invention adopts atechnical solution that provides a back frame of flat panel displaydevice, which comprises primary assembling pieces, secondary assemblingpieces, and a bracing piece for fixing a circuit board; the primaryassembling pieces have a number of at least two, the at least twoprimary assembling pieces being connected through joining, the secondaryassembling pieces being joined to the primary assembling pieces; and thebracing piece comprises a bracing body, a first suspension section, afirst bearing section, and a first resilient bent section, the bracingbody being fixed to the primary assembling pieces or the secondaryassembling pieces or both of the primary assembling pieces and thesecondary assembling pieces, wherein available mounting points betweenthe bracing body and the primary assembling pieces or the secondaryassembling pieces are of a number of at least two so that the bracingpiece is selectively mounted to the back frame at different positions,the first suspension section extending from the bracing body toward oneside of the bracing body, the first bearing section being spaced fromthe bracing body and extending from the first suspension section towardone side of the first suspension section, the first resilient bentsection being located between the first bearing section and the bracingbody and being bent from the first suspension section toward one side ofthe first suspension section, the first bearing section and the firstresilient bent section resiliently clamping a first side edge of thecircuit board.

According to a preferred embodiment of the present invention, the atleast two available mounting points between the bracing body and theprimary assembling pieces or the secondary assembling pieces are twothrough holes, the back frame further comprising a fastener, thefastener being positionable in any one of the at least two through holesand fixing the bracing body to the assembling pieces or the secondaryassembling pieces.

According to a preferred embodiment of the present invention, the atleast two available mounting points between the bracing body and theprimary assembling pieces or the secondary assembling pieces are anelongate through hole, the back frame further comprising a fastener, thefastener being positionable at different positions within the elongatethrough hole and fixing the bracing body to the assembling pieces orsecondary assembling pieces.

According to a preferred embodiment of the present invention, thebracing piece comprises at least two bracing members, the at least twobracing members being joined to form the bracing piece, wherein at leastone of the bracing members is mountable to at least two differentpositions of another bracing member in the lengthwise direction of thebracing piece.

According to a preferred embodiment of the present invention, saidanother bracing member forms at least two through holes that are spacedin the lengthwise direction of the bracing piece, the bracing piecefurther comprising a fastener, the fastener being positionable in anyone of the at least two through holes and fixing said another bracingmember to said at least one of the bracing members.

According to a preferred embodiment of the present invention, saidanother bracing member forms an elongate through hole in the lengthwisedirection of the bracing piece, the bracing piece further comprising afastener, the fastener being positionable at different positions withinthe elongate through hole and fixing said another bracing member to saidat least one of the bracing members.

According to a preferred embodiment of the present invention, thebracing piece further comprises a second suspension section, a secondbearing section, and a second resilient bent section, the secondsuspension section being spaced from the first suspension section andextending from the bracing body toward one side of the bracing body, thesecond bearing section being spaced from the bracing body and extendingfrom the second suspension section toward one side of the secondsuspension section, the second resilient bent section being locatedbetween the second bearing section and the bracing body and extendingfrom the second suspension toward one side of the second suspensionsection, the second bearing section and the second resilient bentsection resiliently clamping a second side edge of the circuit boardthat is opposite to the first side edge.

According to a preferred embodiment of the present invention, the backframe comprises two bracing pieces and the two bracing pieces are spacedfrom each other to clamp different locations of the first side edge andthe second side edge of the circuit board.

According to a preferred embodiment of the present invention, thebracing body is of a step-like configuration and bridges between the twoassembling pieces.

According to a preferred embodiment of the present invention, the backframe comprises at least two primary assembling pieces, the at leas twoprimary assembling pieces being joined to form a main frame structure ofthe back frame, the at least two primary assembling pieces comprising afirst primary assembling piece and a second primary assembling piece,the first primary assembling piece having an end forming at least jointsections that are arranged to space from each other in a lengthwisedirection of the first primary assembling piece, each of the jointsections having a structure mating an end of the second primaryassembling piece, the first primary assembling piece using one of thejoint sections to join the corresponding end of the second primaryassembling piece.

According to a preferred embodiment of the present invention, the jointsections comprise recesses formed in a surface of the first primaryassembling piece and having a shape corresponding to the end of thesecond primary assembling piece for receiving the end of the secondprimary assembling piece.

According to a preferred embodiment of the present invention, the jointsections comprise recesses formed in the surface of the first primaryassembling piece, the second primary assembling piece having a surfaceforming protrusions at corresponding positions that are arranged tospace from each other in a lengthwise direction of the second primaryassembling piece, the protrusions being receivable in the recesses tojoin the first primary assembling piece and the second primaryassembling piece to each other.

According to a preferred embodiment of the present invention, the backframe comprises a third primary assembling piece and a fourth primaryassembling piece; and the first primary assembling piece, the secondprimary assembling piece, the third primary assembling piece, and thefourth primary assembling piece are straight linear and are joined in aleading end-to-tailing end manner to circumferentially form arectangular main frame structure of the back frame.

According to a preferred embodiment of the present invention, the backframe comprises secondary assembling pieces arranged in the main framestructure, the secondary assembling pieces being joined to the mainframe structure.

According to a preferred embodiment of the present invention, thesecondary assembling pieces comprise a first secondary assembling pieceand a second secondary assembling piece, the first secondary assemblingpiece having two ends respectively joined to at least two primaryassembling pieces of the first primary assembling piece, the secondprimary assembling piece, the third primary assembling piece, and thefourth primary assembling piece, the second secondary assembling piecehaving two ends respectively joined to at least two primary assemblingpieces of the first primary assembling piece, the second primaryassembling piece, the third primary assembling piece, and the fourthprimary assembling piece.

According to a preferred embodiment of the present invention, the twoends of the first secondary assembling piece are respectively joined tothe first primary assembling piece and the second primary assemblingpiece that are adjacent to each other and the two ends of the secondsecondary assembling piece are respectively joined to the third primaryassembling piece and the fourth primary assembling piece that areadjacent to each other; or the two ends of the first secondaryassembling piece are respectively joined to the first primary assemblingpiece and the third primary assembling piece that are opposite to eachother and the two ends of the second secondary assembling piece arerespectively joined to the first primary assembling piece and the thirdprimary assembling piece that are opposite to each other.

According to a preferred embodiment of the present invention, the secondprimary assembling piece, the fourth primary assembling piece, the firstsecondary assembling piece, and the second secondary assembling pieceare arranged parallel to each other.

To address the above technical issue, the present invention adopts atechnical solution that provides a backlight system, which comprises alight source, a light homogenization mechanism, and a back frame; andthe back frame carries the light source and the light homogenizationmechanism, the back frame being any back frame described above.

The efficacy of the present invention is that to be distinguished fromthe state of the art, the present invention provides a back frame and abacklight system that use at least two primary assembling pieces ofwhich a first primary assembling piece forms at least two joint sectionsand the first primary assembling piece uses one of the joint sections tojoin a corresponding end of a second primary assembling piece so as tomake a mold for back frame simple in structure, reduce the expenditureof the back frame mold, save the material used for back frame, and thuslower down the cost of flat panel display device. With a bracing piecebeing selectively mounted at different positions in the back frame, asingle bracing piece can meet different requirements for mountingthereby further reducing the manufacturing cost of the flat paneldisplay device. With a circuit board being fixed to a bracing piece, theproblem that the circuit board cannot be easily fixed is overcome.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a conventional back frame of liquidcrystal display device;

FIG. 2 is a schematic view showing a flat panel display device accordingto a first embodiment of the present invention;

FIG. 3 is a schematic view showing a back frame of a flat panel displaydevice according to a second embodiment of the present invention;

FIG. 4 is a schematic view showing a back frame of a flat panel displaydevice according to a third embodiment of the present invention;

FIG. 5 is a schematic view showing a back frame of a flat panel displaydevice according to a fourth embodiment of the present invention;

FIG. 6 is a cross-sectional view showing a joining structure of twoprimary assembling pieces of a flat panel display device according to afifth embodiment of the present invention;

FIG. 7 is a schematic view showing a diagonally-arranged first secondaryassembling piece mounted to a main frame structure of a flat paneldisplay device according to a sixth embodiment of the present invention;

FIG. 8 is a schematic view showing a first secondary assembling pieceand a second secondary assembling piece mounted to a main framestructure of a flat panel display device according to a seventhembodiment of the present invention;

FIG. 9 is a schematic view showing joint sections of a back frame of aflat panel display device according to an eighth embodiment of thepresent invention;

FIG. 10 is a cross-sectional view showing a first example of jointsection of FIG. 9;

FIG. 11 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to aninth embodiment of the present invention;

FIG. 12 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to atenth embodiment of the present invention;

FIG. 13 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to aneleventh embodiment of the present invention;

FIG. 14 is a schematic view showing a joint section of a back frame of aflat panel display device according to a twelfth embodiment of thepresent invention;

FIG. 15 is a schematic view showing joining carried out with differentjoint sections of a back frame of flat panel display device according toa thirteenth embodiment of the present invention;

FIG. 16 is a schematic view showing a portion of a back frame of flatpanel display device according to a fourteenth embodiment of the presentinvention;

FIG. 17 is an enlarged view showing a mounting site of a bracing memberof a back frame and an assembling piece shown in FIG. 16;

FIG. 18 is a cross-sectional view showing the mounting site of thebracing member of the back frame and the assembling piece shown in FIG.16;

FIG. 19 is an enlarged view showing a mounting site of another bracingmember of the back frame and another assembling piece shown in FIG. 16;

FIG. 20 is a cross-sectional view showing the mounting site of saidanother bracing member of the back frame and said another assemblingpiece shown in FIG. 16;

FIG. 21 is an enlarged view showing a mounting site of two bracingmembers of a back frame shown in FIG. 16;

FIG. 22 is a cross-sectional vie showing the mounting site of the twobracing members of the back frame shown in FIG. 16;

FIG. 23 is a schematic view showing a portion of a back frame of flatpanel display device according to a fifteenth embodiment of the presentinvention;

FIG. 24 is a schematic view showing a portion of a back frame of flatpanel display device according to a sixteenth embodiment of the presentinvention;

FIG. 25 is a cross-sectional view showing a bracing piece of the backframe of FIG. 20 and a circuit board;

FIG. 26 is a schematic view showing a back frame of flat panel displaydevice according to a seventeenth embodiment of the present invention;

FIG. 27 is a flow chart showing a method for manufacturing a back frameof a flat panel display device according to an eighteenth of the presentinvention;

FIG. 28 is a schematic view showing a flat panel display device with atouch screen according to a nineteenth embodiment of the presentinvention;

FIG. 29 is a schematic view showing a stereoscopic display deviceaccording to a twentieth embodiment of the present invention; and

FIG. 30 is a schematic view showing a plasma display device according toa twenty-first embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 2-3, FIG. 2 is a schematic view showing a flat paneldisplay device according to a first embodiment of the present inventionand FIG. 3 is a schematic view showing a first embodiment of a backframe of a flat panel display device according to a second embodiment ofthe present invention. As shown in FIG. 2, the flat panel display device20 according to the instant embodiment comprises: a backlight system 21and a display panel 22. The backlight system 21 is arranged on a backside of the display panel 22 and supplies light to the display panel 22.

In the instant embodiment, the backlight system 21 comprises a lightsource 25, a light homogenization mechanism 24, and a back frame 23. Theback frame 23 carries the light source 25 and the light homogenizationmechanism 24. When the backlight system 21 is an edge lighting type, thelight homogenization mechanism 24 is a light guide; and when thebacklight system 21 is a direct type, the light homogenization mechanism24 is a diffuser plate. The back frame 23 comprises at least a firstprimary assembling piece and a second primary assembling piece, and thetwo of at least first and second primary assembling pieces constitute amain frame structure 27 of the back frame 23.

Referring also to FIG. 3, the back frame 23 of the first embodimentcomprises a first primary assembling piece 261 and a second primaryassembling piece 262. The first primary assembling piece 261 has an endjoined to an end of the second primary assembling piece 262, and thefirst primary assembling piece 261 has another end joined to another endof the second primary assembling piece 262 in order to form the mainframe structure 27 of the back frame 23. The first primary assemblingpiece 261 and the second primary assembling piece 262 are both aluminumpieces or galvanized steel pieces. In the instant embodiment, the firstprimary assembling piece 261 and the second primary assembling piece 262are L-shaped.

Referring also to FIG. 4, the back frame 23 of a third embodimentcomprises a first primary assembling piece 281, a second primaryassembling piece 282, and a third primary assembling piece 283. Thethree primary assembling pieces 281, 282, and 283 are assembled andjoined to form a main frame structure 27 of the back frame 23. The threeprimary assembling pieces 281, 282, and 283 are all aluminum pieces orgalvanized steel pieces. An end of the first primary assembling piece281 is joined to an end of the second primary assembling piece 282.Another end of the primary assembling piece 282 is joined to an end ofthe third primary assembling piece 283. Another end of the third primaryassembling piece 282 is joined to another end of the first primaryassembling piece 281.

In the instant embodiment, the first primary assembling piece 281 isL-shaped, and the second and third primary assembling pieces 282, 283are straight linear.

Further, the back frame 23 further comprises secondary assembling piecesarranged inside and joined to the main frame structure 27.

A detailed description will be given to the back frame 23 of the flatpanel display device 20 according to the present invention, whichcomprises four primary assembling pieces and two secondary assemblingpieces.

Referring to FIG. 5, FIG. 5 is a schematic view showing a back frame offlat panel display device according to a fourth embodiment of thepresent invention. As shown in FIG. 5, in the instant embodiment, a backframe 23 comprises: a first primary assembling piece 231, a secondprimary assembling piece 232, a third primary assembling piece 233, afourth primary assembling piece 234, a first secondary assembling piece235, a second secondary assembling piece 236, and bracing pieces 2371,2372, 2373, 2374, 2375, 2376, and 2377. The first primary assemblingpiece 231, the second primary assembling piece 232, the third primaryassembling piece 233, and the fourth primary assembling piece 234 arejoined to each other in a leading end-to-tailing end manner toconstitute a rectangular main frame structure 27 of the back frame 23.The first secondary assembling piece 235 and the second secondaryassembling piece 236, serving as ancillary assembling pieces, arearranged in the main frame structure 27 and joined to the main framestructure 27.

Specifically, an end of the first primary assembling piece 231 is joinedto an end of the second primary assembling piece 232, another end of thesecond primary assembling piece 232 is joined to an end of the thirdprimary assembling piece 233, another end of the third primaryassembling piece 233 is joined to an end of the fourth primaryassembling piece 234, and another end of the fourth primary assemblingpiece 234 is joined to another end of the first primary assembling piece231 in order to form the rectangular main frame structure 27. The firstprimary assembling piece 231, the second primary assembling piece 232,the third primary assembling piece 233, and the fourth primaryassembling piece 234 are all aluminum pieces or galvanized steel pieces.In the instant embodiment, the first primary assembling piece 231, thesecond primary assembling piece 232, the third primary assembling piece233, and the fourth primary assembling piece 234 are straight linear,yet in other embodiments, it is apparent to those skilled in the art tomake all the first primary assembling piece 231, the second primaryassembling piece 232, the third primary assembling piece 233, and thefourth primary assembling piece 234 L-shaped, or some being straightlinear and the remaining being L-shaped. For example, in FIG. 3, thefirst primary assembling piece 261 and the second primary assemblingpiece 262 are both L-shaped; in FIG. 15, the first primary assemblingpiece 281 is L-shaped, while the second and third primary assemblingpieces 282 and 283 are straight linear.

Referring to FIG. 6, FIG. 6 is a cross-sectional view showing a joiningstructure of two primary assembling pieces of a flat panel displaydevice according to a fifth embodiment of the present invention. In theinstant embodiment, the back frame 23 of the flat panel display device20 is formed by joining connection. As shown in FIG. 6, an illustrativeexample is given for the connection of an end of the first primaryassembling piece 231 to an end of the second primary assembling piece232, wherein the end of the second primary assembling piece 232 isjoined to the end of the first primary assembling piece 231 by means offor example screwing, fastening, or welding, to have the end of thesecond primary assembling piece 232 connected to the end of the firstprimary assembling piece 231.

Referring to FIG. 7, FIG. 7 is a schematic view showing adiagonally-arranged first secondary assembling piece mounted to a mainframe structure of a flat panel display device according to a sixthembodiment of the present invention. In the instant embodiment, thefirst secondary assembling piece 235 and the second secondary assemblingpiece 236 are arranged in the main frame structure 27 of the back frame23. An end of the first secondary assembling piece 235 is joined to thefirst primary assembling piece 231 and another end of the firstsecondary assembling piece 235 is joined to the third primary assemblingpiece 233; and an end of the second secondary assembling piece 236 isjoined to the first primary assembling piece 231 and another end of thesecond secondary assembling piece 236 is joined to the third primaryassembling piece 233. Further, the second primary assembling piece 232,the fourth primary assembling piece 234, the first secondary assemblingpiece 235, and the second secondary assembling piece 236 are arrangedparallel to each other. In other embodiments, those skilled in the artmay arrange at least one secondary assembling piece in the main framestructure 27. For example, only the first secondary assembling piece 235is arranged in the main frame structure 27. Further, the two ends of thefirst secondary assembling piece 235 can be selectively joined to atleast two of the primary assembling pieces of the first primaryassembling piece 231, the second primary assembling piece 232, the thirdprimary assembling piece 233, and the fourth primary assembling piece234. For example, the first secondary assembling piece 235 is setdiagonally in the main frame structure 27, as shown in FIG. 7.Similarly, the two ends of the second secondary assembling piece 236 canbe selectively joined to at least two of the primary assembling piecesof the first primary assembling piece 231, the second primary assemblingpiece 232, the third primary assembling piece 233, and the fourthprimary assembling piece 234.

Referring to FIG. 8, FIG. 8 is a schematic view showing a firstsecondary assembling piece and a second secondary assembling piecemounted to a main frame structure of a flat panel display deviceaccording to a seventh embodiment of the present invention. For example,the two ends of the first secondary assembling piece 235 arerespectively joined to the first primary assembling piece 231 and thesecond primary assembling piece 232 that are adjacent to each other andthe two ends of the second secondary assembling piece 236 arerespectively joined the third primary assembling piece 233 and thefourth primary assembling piece 234 that are adjacent to each other.

In the instant embodiment, the back frame 23 comprises seven bracingpieces 2371, 2372, 2373, 2374, 2375, 2376, and 2377. The bracing piece2371 is fixed to the fourth primary assembling piece 234; the bracingpieces 2372, 2373 are both fixed to the first secondary assembling piece235; the bracing piece 2374 is fixed to the second secondary assemblingpiece 236; the bracing piece 2375 is fixed to the second primaryassembling piece 232; and the bracing pieces 2376, 2377 are each fixed,at two ends thereof, to the first secondary assembling piece 235 and thesecond secondary assembling piece 236. In practice, the bracing piecescan be fixed to one or more of the first primary assembling piece 231,the second primary assembling piece 232, the third primary assemblingpiece 233, the fourth primary assembling piece 234, the first secondaryassembling piece 235, and the second secondary assembling piece 236. Inother embodiments, those skilled in the art may mount bracing pieces ofany other numbers to the back frame 23, such as one or more bracingpieces. Further, the bracing pieces can be releasably fixed to one ormore of the first primary assembling piece 231, the second primaryassembling piece 232, the third primary assembling piece 233, the fourthprimary assembling piece 234, the first secondary assembling piece 235,and the second secondary assembling piece 236.

The bracing pieces 2371, 2372, 2373, 2374, 2375, 2376, and 2377 may beprovided with bumps (not labeled) so that the back frame 23 may fixcomponents, such as circuit boards, with such bumps.

Molds for making the back frame 23 will be described. In the instantembodiment, the first primary assembling piece 231 and the third primaryassembling piece 233 are of the same size and shape so that they can bemade by stamping with the same mold. The second primary assembling piece232, the fourth primary assembling piece 234, the first secondaryassembling piece 235, and the second secondary assembling piece 236 areof the same size and shape so that they can be made by stamping with thesame mold, making it possible to share the mold. Thus, the back frame 23of the present invention can be made by stamping with only twosmall-sized molds, and compared to the conventional back frame 10 thatrequires a large-sized mold, the molds for making the back frame 23 ofthe present invention are simple in structure and small in size and thusthe cost of mold for the back frame 23 can be lowered. Further, comparedto the whole back frame structure of the conventional back frame 10, theback frame 23 of the present invention can significantly save materialused and thus reduce the manufacturing cost of the flat panel displaydevice 20.

Referring to FIG. 9, FIG. 9 is a schematic view showing joint sectionsof a back frame of a flat panel display device according to an eighthembodiment of the present invention. As shown in FIG. 9, in the instantembodiment, an end of the first primary assembling piece is providedwith two joint sections, and the joint sections have a structure matingan end of the second primary assembling piece so that the first primaryassembling piece can be joined to a corresponding end of the secondprimary assembling piece.

Specifically, the first primary assembling piece 231 has an end having asurface forming joint sections 2311, 2312, and the joint sections 2311,2312 are arranged in a spaced manner in a lengthwise direction of thefirst primary assembling piece 231. The joint sections 2311, 2312 areformed by forming recesses having a shape mating an end of the secondprimary assembling piece 232 in the first primary assembling piece 231in order to receive the end of the second primary assembling piece 232therein.

Referring to FIG. 10, FIG. 10 is a cross-sectional view showing a firstexample of joint section of FIG. 9. As shown in FIG. 10, the jointsections 2311, 2312 are recesses that do not extend through oppositesurfaces of the end of the first primary assembling piece 231 and therecesses are of a rectangular shape with the second primary assemblingpiece 232 being straight linear.

To assemble a large-sized back frame 23, the joint section 2311 that isclose to the very end of the first primary assembling piece 231 is firsttaken and a second primary assembling piece 232 having a correspondingwidth is selected. Afterwards, an end of the second primary assemblingpiece 232 is positioned in the recess of the joint section 2311. Andthen, means, such as screwing, fastening, or welding, is applied to joinand fix the end of the second primary assembling piece 232 to the jointsection 2311. To assemble a small-sized back frame 23, the joint section2312 that is distant from the very end of the first primary assemblingpiece 231 is first chosen and a second primary assembling piece 232having a corresponding width is selected. Afterwards, an end of thesecond primary assembling piece 232 is positioned in the recess of thejoint section 2312. And then, means, such as screwing, fastening, orwelding, is applied to join and fix the end of the second primaryassembling piece 232 to the joint section 2312.

Referring to FIG. 11, FIG. 11 is a schematic view showing a joiningstructure of a joint section of a back frame of a flat panel displaydevice according to a ninth embodiment of the present invention. Asshown in FIG. 11, to allow of selection of the size of the back frame 23in another direction, for example the second primary assembling piece232 forms a protrusion at a corresponding location on a surface thereof,and the protrusion of the second primary assembling piece 232 isembedded in the recess the first primary assembling piece 231 at acorresponding location in order to join the first primary assemblingpiece 231 and the second primary assembling piece 232. Further, thesecond primary assembling piece 232 may form, on a surface of one endthereof, at least two protrusions that are spaced in the lengthwisedirection of the second primary assembling piece 232, such as two,three, or four protrusions.

Furthermore, as shown in FIG. 12, FIG. 12 is a schematic view showing ajoining structure of a joint section of a back frame of a flat paneldisplay device according to a tenth embodiment of the present invention.The recess of the first primary assembling piece 231 can be a recess ofa multi-stepped configuration and the second primary assembling piece232 forms, at a corresponding location, a protrusion having amulti-stepped configuration corresponding to the recess.

Further, as shown in FIG. 13, FIG. 13 is a schematic view showing ajoining structure of a joint section of a back frame of a flat paneldisplay device according to an eleventh embodiment of the presentinvention. Taking the joint section 2311 as an example, the recess ofthe first primary assembling piece 231 forms, in a bottom thereof, afirst through hole 2313, and the second primary assembling piece 232forms, at a location corresponding to the joint section 2311, a secondthrough hole 2321. The back frame 23 further comprises a fastener 240.The fastener 240 extends through the first through hole 2313 and thesecond through hole 2321 to joint the first primary assembling piece 231and the second primary assembling piece 232 to each other.

As shown in FIG. 14, FIG. 14 is a schematic view showing a joint sectionof a back frame of a flat panel display device according to a twelfthembodiment of the present invention. The recesses of the joint sections2311, 2312 of the first primary assembling piece 231 are of a circularshape. Yet, in other embodiments, those skilled in the art may arrangethe shape of the recesses to be other polygonal configurations, such astriangle.

As shown in FIG. 15, FIG. 15 is a schematic view showing joiningrealized by using different joint sections of a back frame of a flatpanel display device according to a thirteenth embodiment of the presentinvention. In another embodiment of the back frame of flat panel displaydevice according to the present invention, the joint sections 2311, 2312are recesses that extend through opposite surfaces of the first primaryassembling piece 231, whereby an end of the second primary assemblingpiece 232 is movable within the joint sections 2311, 2312. For example,after the end of the second primary assembling piece 232 is setextending beyond and joined and fixed to the joint section 2312, theportion of extension is then trimmed off so that the length of thesecond primary assembling piece 232 that serves as a primary assemblingpiece of the back frame can be adjusted and thus back frames ofdifferent sizes can be obtained.

In a practical application, the other end of the first primaryassembling piece 231 and both ends of the third primary assembling piece233 are all provided with two joint sections having a structureidentical to that of the joint sections 2311, 2312. The ends of thesecond primary assembling piece 232 and the ends of the fourth primaryassembling piece 234 may be subjected to specific designs or no designat all according to different applications. For example:

(1) In a first situation, as shown in FIG. 10, the two ends of thesecond primary assembling piece 232 and the two ends of the fourthprimary assembling piece 234 are of no specific design. In other words,the ends are of the same structure as the remaining portions. Under thiscondition, in making a join with a selected joint section 2311 (2312) atone end of the first primary assembling piece 231 (the same applicableto the other end), if an attempt is made to change the width of the backframe 23, then the length of the corresponding second primary assemblingpiece 232 and fourth primary assembling piece 234 must be selectedaccordingly. Namely, if the joint section 2311 that is close to the veryend of the first primary assembling piece 231 is selected for joining,then no trimming is applied to the second primary assembling piece 232and the fourth primary assembling piece 234 or the portion that istrimmed off is short; if the joint section 2312 that is distant from thevery end of the first primary assembling piece 231 is selected forjoining, then the second primary assembling piece 232 and the fourthprimary assembling piece 234 are trimmed and the trimmed portion beinglong or short is according to the distance that the joint section isfrom the very end of the first primary assembling piece 231 being greator small; and

(2) In a second situation, it is similar to the first situation, but asshown in FIG. 11, the second primary assembling piece 232 and the fourthprimary assembling piece 234 use different protrusions to respectivelymate the first primary assembling piece 231 and the third primaryassembling piece 233 in order to realize change of width of the backframe 23; similarly, if a joint section 2312 other than the first jointsection 2311 that is close to the very end of the first primaryassembling piece 231 is selected for joining, then before or afterjoining, excessive portions of the second primary assembling piece 232and the fourth primary assembling piece 234 may be trimmed off.

This also applicable to an embodiment of the main frame structure 27 ofthe back frame 23 that is formed by only joining two L-shaped primaryassembling pieces.

In summary, the present invention provides a back frame 23 having afirst primary assembling piece that is provided with at least two jointsections. The number of the joint section can be selected according tothe requirement of customers. In the instant embodiment, a descriptionis given to an example comprising two joint sections 2311, 2312. Thus,to prepare the molds for making the back frame 23, only two sets of moldare needed, namely one mold for a first primary assembling piece and theother mold for a second primary assembling piece. The first primaryassembling piece may be provided with a plurality of joint sections forjoining operation in order to form various sizes for the back frame 23.To assemble the back frame 23, based on the desired size of the backframe 23, the corresponding one of the joint sections is selected. Withthe joint section, the second primary assembling piece is joined to thejoint section of the first primary assembling piece and the other jointsection of the first primary assembling piece that is located outward ofthe joining location of the second primary assembling piece is trimmedoff to obtain a desired size of the back frame 23. Compared to theconventional technology that requires different back frame molds formaking different sizes of back frame 10, the back frame of the flatpanel display device 23 according to the present invention requires onlya mold for the first primary assembling piece and a mold for the secondprimary assembling piece 28 so that mold sharing among various sizes ofproduct can be realized and the molds used are of simple structures,allowing of reduction of expenditure of the molds for back frames.

The present invention also provides a mold for making a back frame offlat panel display device. The back frame mold is provided with a mainpattern for forming a primary assembling piece of the back frame and themain pattern comprises a sub-pattern that forms at least two jointsections on an end of the primary assembling piece. The primaryassembling piece comprises the previously discussed first primaryassembling piece and second primary assembling piece, corresponding tothe above mentioned main pattern; and the joint section comprises thepreviously discussed joint section of the first primary assemblingpiece, corresponding to the above mentioned sub-pattern. Repeateddescription is omitted herein.

The present invention also provides a bracing piece that is applicableto the back frame discussed in each of the previous embodiment, whereinthe bracing piece can be mounted to fixed to the primary assemblingpieces or the secondary assembling pieces, and the primary assemblingpieces or the secondary assembling pieces can be mounted to at least twodifferent positions of the bracing piece in a lengthwise direction ofthe bracing piece so that the bracing piece is movable to allow theposition of a bump formed on the bracing piece for positioning purposeto be adjustable and thus meeting different requirements of the backframe for mounting. In the following illustration, the assembling piecescan be the primary assembling pieces or the secondary assembling pieces,and no specific distinction will be made in the illustration.

Specifically, as shown in FIG. 16, in the instant embodiment, thebracing piece 60 is formed by joining bracing members 601, 602. Two endsof the bracing piece 60 are respectively fixed to assembling pieces 61,62. The assembling pieces 61, 62 are mountable to the bracing piece 60in at least two different positions in the lengthwise direction of thebracing piece 60, wherein the assembling pieces 61, 62 can be theprimary assembling pieces or the secondary assembling pieces of each ofthe above embodiments. In other backup embodiments, the bracing piece 60may has only one end fixed to the assembling piece, while the other endis arranged in a suspending form. The bracing piece 60 may also be of aunitary design.

Further as shown in FIGS. 17-18, formed in an end of the bracing member601 that is fixed to the assembling piece 61 is an elongate through hole6011 that is arranged in the bracing member 601 in the lengthwisedirection of the bracing piece 60. The bracing member 601 is fixed by ascrew 63 to the assembling piece 61 of the back frame. The screw 63 ispositionable in different locations within the elongate through hole6011. Thus, in assembling, the elongate through hole 6011 is put tooverlap a threaded hole 611 of the assembling piece 61 and according tothe need for mounting, the position of the bracing member 601 on theassembling piece 61 is adjusted in the lengthwise direction of thebracing piece 60 so as to adjust the position of the bump 6012 of thebracing member 601 with respect to the assembling piece 61. After thebump 6012 of the bracing member 601 has been adjusted to a desiredposition, the screw 63 is set in a corresponding position within theelongate through hole 6011 and engages the threaded hole 611 of theassembling pieces 61 to thereby fix the bracing member 601 to theassembling piece 61.

Similarly, further as shown in FIGS. 19-20, in an end of the bracingmember 602 that is fixed to the assembling piece 62, an elongate throughhole 6021 is formed in the lengthwise direction of the bracing piece 60.A screw 64 is positionable in different positions within the elongatethrough hole 6021, whereby by having the screw 64 engaging a threadedhole 621 of the assembling piece 62, the bracing member 602 is fixed tothe assembling piece 62, so as to realize position adjustment of a bump6022 with respect to the assembling piece 62.

Further as shown in FIGS. 21-22, in ends of the bracing member 601 andthe bracing member 602 that are fixed to each other, an elongate throughhole 6013 is formed in the bracing member 601 in the lengthwisedirection of the bracing piece 60, and an the elongate through hole 6023is formed in the bracing member 602 in the lengthwise direction of thebracing piece 60. The bracing member 601 is fixed by a screw 65 to thebracing member 602. The screw 65 can be set at any position within theelongate through holes 6013, 6023. In assembling, the elongate throughholes 6013, 6023 are set to overlap each other and the positions of thebracing pieces 601 and 602 in the lengthwise direction of the bracingpiece 60 are adjusted according to the needs for mounting so as toadjust the positions of bumps 6012, 6022 with respect to the assemblingpieces 61, 62 (see FIG. 16) and the length of the bracing piece 60.After the adjustment of position, the screw 65 is set to a correspondingposition between the elongate through holes 6013 and 6023 and screwingis carried out to fix the bracing member 601 to the bracing member 602.In other backup embodiments, the screws 63, 64, 65 can be replaced byother fasteners, such as rivets and bolts.

As shown in FIG. 23, in the instant embodiment, the bracing piece formsat least two through holes that are spaced in the lengthwise directionof the bracing piece to replace the elongate through hole of the aboveembodiments. Specifically, in the end of the bracing member 701 that isfixed to the assembling piece 71, a plurality of through holes 7014,7015, 7016 is arranged in the lengthwise direction of the bracing piece70. A screw (not shown) can be set in one of the through holes 7014,7015, 7016 and engages a threaded hole 711 defined in the assemblingpiece 71 so as to fix the bracing member 701 to the assembling piece 71,thereby realizing position adjustment of a bump 7012 with respect to theassembling piece 71.

Similarly, in an end of the bracing member 702 that is fixed to theassembling piece 72, a plurality of through holes 7024, 7025, 7026 isarranged in the lengthwise direction of the bracing piece 70. A screw(not shown) can be set in one of the through holes 7024, 7025, 7026 andengages a threaded hole 721 defined in the assembling piece 72 so as tofix the bracing member 702 to the assembling piece 72, thereby realizingposition adjustment of a bump 7022 with respect to the assembling piece72.

Further, in ends of the bracing member 701 and the bracing member 702that are fixed to each other, a plurality of through holes 7017, 7018,7019 is arranged in the bracing member 701 in the lengthwise directionof the bracing piece 70 and a plurality of through holes 7027, 7028,7029 is arranged in the bracing member 702 in the lengthwise directionof the bracing piece 70. A screw (not shown) can be set in any of theplurality of through holes 7017, 7018, 7019 and any one of the pluralityof through holes 7027, 7028, 7029. In assembling, the positions of thebracing members 701 and 702 in the lengthwise direction of the bracingpiece are adjusted according to the needs for mounting and correspondingones of the through holes are set to overlap each other so as to adjustthe positions of bumps 7012, 7022 with respect to the assembling pieces71, 72 and the length of the bracing piece 70. After the positionadjustment, a screw is set to the overlapped position of correspondingthrough holes to carry out screwing so as to fix the bracing member 701to the bracing member 702.

Certainly, in the above embodiments, those skilled in the art may form aplurality of through holes or an elongate through hole in the primaryassembling pieces or the secondary assembling pieces and the bracingpiece can be mounted to different positions of the primary assemblingpieces or the secondary assembling pieces according to the requirementsof mounting so that position adjustability of a bump with respect to theprimary assembling pieces or the secondary assembling pieces can berealized. Specific description will not be given again here.

In the above embodiments, the bracing piece is fixed by screws to theassembling pieces, but those having ordinary skills in the art mayeasily contemplate that fasteners, such as rivets, can be used forfixing. The present invention imposes no specific limitation in thisrespect.

With the above discussed manners, the present invention provides a backframe and a backlight system that comprises assembling pieces that arejoined to form a back frame so as to make a mold for back frame simplein structure, reduce the expenditure for mold of back frame, save thematerial used for back frame, and thus lower down the cost of flat paneldisplay device. Further, with the mounting position of the bracing pieceto the assembling piece being made adjustable in a lengthwise directionof the bracing piece, a single bracing piece can meet differentrequirements for mounting to thereby reducing the manufacturing cost offlat panel display device.

The present invention also provides a bracing piece that is applicableto each of the above discussed embodiments and is mounted to theassembling pieces for fixing a circuit board. Referring to FIGS. 24-25,assembling pieces 71, 72, and 73 are the various assembling piecesdescribed in the above discussed embodiments, including the primaryassembling pieces that are joined to form a main frame structure or thesecondary assembling pieces that are arranged inside the main framestructure and joined to the main frame structure. A bracing piece 50comprises a bracing body 51, a first suspension section 52, a firstbearing section 53, and a first resilient bent section 54. The bracingbody 51 is fixed to the assembling pieces 71 and 72. In the instantembodiment, the bracing body 51 is of a step-like configuration andbridges between the two assembling pieces 71, 72. However, in backupembodiments of the present invention, the bracing body 51 can be of astraight bar like configuration or other shapes. Further, the bracingbody 51 can be fixed to the assembling piece with only one end thereof,while the other end is arranged in a suspending form to simplifymounting process.

The first suspension section 52 extends from the bracing body 51 towardone side of the bracing body 51. The first bearing section 53 is spacedfrom the bracing body 51 and extends from the first suspension section52 toward one side of the first suspension section 52. The firstresilient bent section 54 is located between the first bearing section52 and the bracing body 51 and is bent from the first suspension section52 toward one side of the first suspension section 52. The first bearingsection 53 and the first resilient bent section 54 resiliently clamp afirst side edge of a circuit board 80.

Referring to FIG. 25, the bracing piece 50 further comprises a secondsuspension section 52′, a second bearing section 53′, and a secondresilient bent section 54′. The second suspension section 52′ is spacedfrom the first suspension section 52 and extends from the bracing body51 toward one side of the bracing body 51. The second bearing section53′ is spaced from the bracing body 51 and extends from the secondsuspension section 52′ toward one side of the second suspension section52′. The second resilient bent section 54′ is located between the secondbearing section 53′ and the bracing body 51 and is bent from the secondsuspension section 52′ toward one side of the second suspension section52′. The second bearing section 53′ and the second resilient bentsection 54′ resiliently clamp a second side edge of the circuit board 80that is opposite to the first side edge. In a preferred embodiment, thefirst suspension section 52, the first bearing section 53, and the firstresilient bent section 54 and the second suspension section 52′, thesecond bearing section 53′, and the second resilient bent section 54′are symmetric with respect to a center line of the bracing body 51. In abackup embodiment of the present invention, the bracing body 51 of thebracing piece 50 may comprise only the first suspension section 52, thefirst bearing section 53, and the first resilient bent section 54 foronly resiliently clamping the first side edge of the circuit board 80,and an additional bracing piece that is identical to the bracing piece50 is provided to resiliently clamp the second side edge of the circuitboard 80.

Referring to FIG. 25, after the circuit board 80 is mounted, anelectromagnetic shielding piece 100 is set on the bracing body 51. Theelectromagnetic shielding piece 100 is spaced from the circuit board 80to shield electromagnetic signals generated by the circuit board 80. Theelectromagnetic shielding piece 100 can be a Faraday cage or a metalplate.

Referring to FIG. 24, in the instant embodiment, a bracing piece 90 thatis identical in structure to the bracing piece 50 is further provided.The bracing piece 90 is spaced from the bracing piece 50 to clampdifferent locations of the first and second side edges of the circuitboard 80.

With the above discussed manners, the present invention provides a backframe and a backlight system that comprises assembling pieces thatemploys a joining process to form a back frame so as to make the backframe simple in structure, save the material used for back frame, andthus lower down the manufacturing cost of backlighting display device.Further, with a bracing piece that comprises a bracing body, a firstsuspension section, a first bearing section, and a first resilient bentsection being used to fix a circuit board, the cost of mold is reducedand the problem that a circuit board cannot be easily fixed is overcome.

As shown in FIG. 26, which is a schematic view showing an embodiment ofthe present invention that combines all features associated with backframe joining, adjustability, and fixing of PCB, assembling pieces 71and 72 are various assembling pieces shown in the above discussedembodiments and comprise the primary assembling pieces that are joinedto form a main frame structure of the back frame or the secondaryassembling pieces that are arranged inside the main frame structure andjoined to the main frame structure. In the instant embodiment, thebracing piece comprises a bracing body, a first suspension section, afirst bearing section, and a first resilient bent section, and thebracing body is mounted to the primary assembling pieces or thesecondary assembling pieces or is mounted to both the primary assemblingpieces and the secondary assembling pieces, wherein available mountingpoints between the bracing body and the assembling pieces are of anumber of at least two so that the bracing piece is selectively mountedto the back frame at different positions. As shown in FIG. 26, thebracing piece 50 has two ends respectively fixed to the assemblingpieces 71, 72. The bracing piece 50 comprises a bracing body 51, a firstsuspension section 52, a first bearing section 53, and a first resilientbent section 54. The assembling piece 72 can be mounted to at least twodifferent positions of the bracing piece 50 in a lengthwise direction ofthe bracing piece 50 and the bracing piece 50 can be mounted to at leasttwo different positions of the assembling piece 72 in a lengthwisedirection of the assembling piece 72.

As shown in FIG. 27, the present invention also provides a method formaking a back frame of flat panel display device. The method comprisesthe following steps:

Step 501: manufacturing at least first and second primary assemblingpieces, in which the first primary assembling piece has an end formingat least two joint sections, each of the joint sections having astructure that mates a corresponding end of the second primaryassembling piece; and

Step 502: selecting one joint section of the at least two joint sectionsaccording to a size of the back frame to join the corresponding end ofthe second primary assembling piece.

In the instant embodiment, when other joint sections are present betweenthe joining location of the second primary assembling piece and the endof the first primary assembling piece, before or after the step ofselecting one joint section of the at least two joint sections accordingto a size of the back frame to join the corresponding end of the secondprimary assembling piece, the other joint sections of the first primaryassembling piece that are located outward of the joining position of thesecond primary assembling piece are trimmed off. The first primaryassembling piece comprises the previously discussed first primaryassembling piece, and the second primary assembling piece comprises thepreviously discussed second primary assembling piece, and repeateddescription will be omitted herein.

As shown in FIG. 28, the flat panel display device 20 of the presentinvention further comprises a touch screen 29. The touch screen 29 isarranged on a light exit surface of the display panel 22 of the flatpanel display device 20. The flat panel display device 20 comprises: thebacklight system 21 and the above discussed display panel 22. Thebacklight system 21 is arranged at the back side of the display panel 22and supplies light to the display panel 22.

The backlight system 21 comprises a light source 25, a lighthomogenization mechanism 24, and a back frame 23. The back frame 23carries the light source 25 and the light homogenization mechanism 24.When the backlight system 21 is an edge lighting type, the lighthomogenization mechanism 24 is a light guide; and when the backlightsystem 21 is a direct type, the light homogenization mechanism 24 is adiffuser plate. The back frame 23 comprises at least a first primaryassembling piece and a second primary assembling piece, and the at leastone first and second primary assembling pieces constitute a main framestructure 27 of the back frame 23.

It is apparent that the backlight system 21 can be of a structure of anyone of the previously discussed embodiments of the backlight system.

It is noted that the flat panel display device 20 of the presentinvention can be a liquid crystal display device or a liquid crystaltelevision.

The present invention also provides a stereoscopic display device 30, asshown in FIG. 29. The stereoscopic display device 30 comprises a liquidcrystal lens grating 31, a backlight system 32, and a display panel 33.The liquid crystal lens grating 31 is arranged on a light exit surfaceof the display panel 33. The backlight system 32 can be a backlightsystem of one of the above discussed embodiments, such as the backlightsystem 32 comprising the back frame 23. The back frame 23 comprises atleast first primary assembling piece and the second primary assemblingpiece. The at least first and second primary assembling pieces form amain frame structure of the back frame. The backlight system 32 can beof a structure of any of the previously discussed embodiments ofbacklight system and repeated description will be omitted herein.

The present invention also provides a plasma display device 40, as shownin FIG. 30. The plasma display device 40 comprises a plasma displaypanel 41 and a back frame 42. The back frame 42 is arranged at a backside of the display panel 41. The back frame 42 can be the back frame ofany of the previously discussed embodiments and repeated descriptionwill be omitted herein.

With the above discussed manners, the present invention provides a flatpanel display device, a stereoscopic display device, and a plasmadisplay device that have a mold for back frame that is of a simplestructure, reduce the expenditure for mold of back frame, and also savethe material used for back frame so as to lower down the cost of flatpanel display device.

Embodiments of the present invention have been described, but are notintending to impose any undue constraint to the appended claims of thepresent invention. Any modification of equivalent structure orequivalent process made according to the disclosure and drawings of thepresent invention, or any application thereof, directly or indirectly,to other related fields of technique, is considered encompassed in thescope of protection defined by the claims of the present invention.

What is claimed is:
 1. A back frame of a flat panel display device, wherein: the back frame comprises primary assembling pieces, secondary assembling pieces, and a bracing piece for fixing a circuit board having at least one major surface defining a normal direction; the primary assembling pieces have a number of at least two, the at least two primary assembling pieces being connected through joining, the secondary assembling pieces being joined to the primary assembling pieces; the bracing piece comprises a bracing body, a first suspension section and a second suspension section, a first bearing section and a second bearing section, and a first resilient bent section and a second resilient bent section, the bracing body being mounted to the primary assembling pieces or the secondary assembling pieces or mounted to both the primary assembling pieces and the secondary assembling pieces, wherein available mounting points between the bracing body and the primary assembling pieces or the secondary assembling pieces are of a number of at least two so that the bracing piece is selectively mounted to the back frame at different positions; and the first suspension section and second suspension section extend from the bracing body toward one side of the bracing body to be spaced from and opposing each other so as to define therebetween a receiving space for receiving the circuit board therein in such a way that the first and second suspension sections respectively engage first and second opposite side edges of the circuit board by having the circuit board moved into the space in a predetermined direction substantially parallel to the normal direction of the circuit board, the first bearing section and second bearing section being spaced from the bracing body and respectively extending from the first suspension section and the second suspension section to collectively receive the circuit board to be positioned thereon, the first resilient bent section and the second resilient bent section being respectively located between the first and second bearing sections and the bracing body and being respectively bent from the first and second suspension sections toward each other to define a passage having a size smaller than the receiving space, whereby when the circuit board is moved in the predetermined direction substantially parallel to the normal direction of the circuit board to reach and be positioned on the first and second bearing sections, the first bearing section and the first resilient bent section resiliently clamp the first side edge of the circuit board and the second bearing section and the second resilient bent section resiliently clamp the second side edge of the circuit board so as to clamp the circuit board between the first and second suspension sections of the bracing piece.
 2. The back frame as claimed in claim 1, wherein the at least two available mounting points between the bracing body and the primary assembling pieces or the secondary assembling pieces are two through holes, the back frame further comprising a fastener, the fastener being positionable in any one of the at least two through holes and fixing the bracing body to the primary assembling pieces or the secondary assembling pieces.
 3. The back frame as claimed in claim 1, wherein the at least two available mounting points between the bracing body and the primary assembling pieces or the secondary assembling pieces are an elongate through hole, the back frame further comprising a fastener, the fastener being positionable at different positions within the elongate through hole and fixing the bracing body to the primary assembling pieces or secondary assembling pieces.
 4. The back frame as claimed in claim 1, wherein the bracing piece comprises at least two bracing members including a first bracing member and a second bracing member, the at least two bracing members being joined to form the bracing piece, wherein the first bracing member is mountable to at least two different positions of the second bracing member in the lengthwise direction of the bracing piece.
 5. The back frame as claimed in claim 4, wherein the second bracing member forms at least two through holes that are spaced in the lengthwise direction of the bracing piece, the bracing piece further comprising a fastener, the fastener being positionable in one of the at least two through holes and fixing the second bracing member to the first bracing member.
 6. The back frame as claimed in claim 4, wherein the second bracing member forms an elongate through hole in the lengthwise direction of the bracing piece, the bracing piece further comprising a fastener, the fastener being positionable at different positions within the elongate through hole and fixing the second bracing member to the first bracing member.
 7. The back frame as claimed in claim 1, wherein the second suspension section being spaced from the first suspension section and extending from the bracing body toward one side of the bracing body, the second bearing section being spaced from the bracing body and extending from the second suspension section toward one side of the second suspension section, the second resilient bent section being located between the second bearing section and the bracing body and extending from the second suspension section toward one side of the second suspension section, the second bearing section and the second resilient bent section resiliently clamping the second side edge of the circuit board that is opposite to the first side edge.
 8. The back frame as claimed in claim 7, wherein the back frame comprises two bracing pieces and the two bracing pieces are spaced from each other to clamp different locations of the first side edge and the second side edge of the circuit board.
 9. The back frame as claimed in claim 8, wherein the bracing body is of a step-like configuration and bridges between the two assembling pieces.
 10. The back frame as claimed in claim 1, wherein: the at least two primary assembling pieces comprise a first primary assembling piece and a second primary assembling piece, the first primary assembling piece having an end forming at least joint sections that are arranged to space from each other in a lengthwise direction of the first primary assembling piece, each of the joint sections having a structure mating an end of the second primary assembling piece, the first primary assembling piece using one of the joint sections to join the corresponding end of the second primary assembling piece.
 11. The back frame as claimed in claim 10, wherein: the joint sections comprise recesses formed in a surface of the first primary assembling piece and having a shape corresponding to the end of the second primary assembling piece for receiving the end of the second primary assembling piece.
 12. The back frame as claimed in claim 10, wherein: the joint sections comprise recesses formed in the surface of the first primary assembling piece, the second primary assembling piece having a surface forming protrusions at corresponding positions that are arranged to space from each other in a lengthwise direction of the second primary assembling piece, the protrusions being receivable in the recesses to join the first primary assembling piece and the second primary assembling piece to each other.
 13. The back frame as claimed in claim 10, wherein: the back frame comprises a third primary assembling piece and a fourth primary assembling piece; and the first primary assembling piece, the second primary assembling piece, the third primary assembling piece, and the fourth primary assembling piece are straight linear and are joined in a leading end-to-tailing end manner to circumferentially form a rectangular main frame structure of the back frame.
 14. The back frame as claimed in claim 13, wherein: the back frame comprises secondary assembling pieces arranged in the main frame structure, the secondary assembling pieces being joined to the main frame structure, the secondary assembling pieces comprising a first secondary assembling piece and a second secondary assembling piece, the first secondary assembling piece having two ends respectively joined to at least two primary assembling pieces of the first primary assembling piece, the second primary assembling piece, the third primary assembling piece, and the fourth primary assembling piece, the second secondary assembling piece having two ends respectively joined to at least two primary assembling pieces of the first primary assembling piece, the second primary assembling piece, the third primary assembling piece, and the fourth primary assembling piece.
 15. The back frame as claimed in claim 14, wherein: the two ends of the first secondary assembling piece are respectively joined to the first primary assembling piece and the second primary assembling piece that are adjacent to each other and the two ends of the second secondary assembling piece are respectively joined to the third primary assembling piece and the fourth primary assembling piece that are adjacent to each other; or the two ends of the first secondary assembling piece are respectively joined to the first primary assembling piece and the third primary assembling piece that are opposite to each other and the two ends of the second secondary assembling piece are respectively joined to the first primary assembling piece and the third primary assembling piece that are opposite to each other, the second primary assembling piece, the fourth primary assembling piece, the first secondary assembling piece, and the second secondary assembling piece being arranged parallel to each other.
 16. A backlight system, wherein: the backlight system comprises a light source, a light homogenization mechanism, and a back frame; and the back frame carries the light source and the light homogenization mechanism, the back frame being a back frame claimed in claim
 1. 